/*
 * Copyright 2002-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.security.samples.config;

import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.converter.RsaKeyConverters;
import org.springframework.security.saml2.credentials.Saml2X509Credential;
import org.springframework.security.saml2.provider.service.registration.InMemoryRelyingPartyRegistrationRepository;
import org.springframework.security.saml2.provider.service.registration.RelyingPartyRegistration;
import org.springframework.security.saml2.provider.service.servlet.filter.Saml2WebSsoAuthenticationFilter;

import java.io.ByteArrayInputStream;
import java.nio.charset.StandardCharsets;
import java.security.PrivateKey;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;

import static org.springframework.security.saml2.credentials.Saml2X509Credential.Saml2X509CredentialType.DECRYPTION;
import static org.springframework.security.saml2.credentials.Saml2X509Credential.Saml2X509CredentialType.SIGNING;
import static org.springframework.security.saml2.credentials.Saml2X509Credential.Saml2X509CredentialType.VERIFICATION;

@EnableWebSecurity
@EnableGlobalMethodSecurity(prePostEnabled = true)
public class SecurityConfig extends WebSecurityConfigurerAdapter {

	RelyingPartyRegistration getSaml2AuthenticationConfiguration() throws Exception {
		//remote IDP entity ID
		String idpEntityId = "https://simplesaml-for-spring-saml.cfapps.io/saml2/idp/metadata.php";
		//remote WebSSO Endpoint - Where to Send AuthNRequests to
		String webSsoEndpoint = "https://simplesaml-for-spring-saml.cfapps.io/saml2/idp/SSOService.php";
		//local registration ID
		String registrationId = "simplesamlphp";
		//local entity ID - autogenerated based on URL
		String localEntityIdTemplate = "{baseUrl}/saml2/service-provider-metadata/{registrationId}";
		//local signing (and decryption key)
		Saml2X509Credential signingCredential = getSigningCredential();
		//IDP certificate for verification of incoming messages
		Saml2X509Credential idpVerificationCertificate = getVerificationCertificate();
		String acsUrlTemplate = "{baseUrl}" + Saml2WebSsoAuthenticationFilter.DEFAULT_FILTER_PROCESSES_URI;
		return RelyingPartyRegistration.withRegistrationId(registrationId)
				.providerDetails(config -> config.entityId(idpEntityId))
				.providerDetails(config -> config.webSsoUrl(webSsoEndpoint))
				.credentials(c -> c.add(signingCredential))
				.credentials(c -> c.add(idpVerificationCertificate))
				.localEntityIdTemplate(localEntityIdTemplate)
				.assertionConsumerServiceUrlTemplate(acsUrlTemplate)
				.build();
	}

	@Override
	protected void configure(HttpSecurity http) throws Exception {
		// @formatter:off
		http
			.authorizeRequests()
				.anyRequest().authenticated()
				.and()
			.saml2Login()
				.relyingPartyRegistrationRepository(
						new InMemoryRelyingPartyRegistrationRepository(
							getSaml2AuthenticationConfiguration()
					)
				)
				.loginProcessingUrl("/sample/jc/saml2/sso/{registrationId}")
		;
		// @formatter:on
	}

	private Saml2X509Credential getVerificationCertificate() {
		String certificate = "-----BEGIN CERTIFICATE-----\n" +
				"MIIEEzCCAvugAwIBAgIJAIc1qzLrv+5nMA0GCSqGSIb3DQEBCwUAMIGfMQswCQYD\n" +
				"VQQGEwJVUzELMAkGA1UECAwCQ08xFDASBgNVBAcMC0Nhc3RsZSBSb2NrMRwwGgYD\n" +
				"VQQKDBNTYW1sIFRlc3RpbmcgU2VydmVyMQswCQYDVQQLDAJJVDEgMB4GA1UEAwwX\n" +
				"c2ltcGxlc2FtbHBocC5jZmFwcHMuaW8xIDAeBgkqhkiG9w0BCQEWEWZoYW5pa0Bw\n" +
				"aXZvdGFsLmlvMB4XDTE1MDIyMzIyNDUwM1oXDTI1MDIyMjIyNDUwM1owgZ8xCzAJ\n" +
				"BgNVBAYTAlVTMQswCQYDVQQIDAJDTzEUMBIGA1UEBwwLQ2FzdGxlIFJvY2sxHDAa\n" +
				"BgNVBAoME1NhbWwgVGVzdGluZyBTZXJ2ZXIxCzAJBgNVBAsMAklUMSAwHgYDVQQD\n" +
				"DBdzaW1wbGVzYW1scGhwLmNmYXBwcy5pbzEgMB4GCSqGSIb3DQEJARYRZmhhbmlr\n" +
				"QHBpdm90YWwuaW8wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQC4cn62\n" +
				"E1xLqpN34PmbrKBbkOXFjzWgJ9b+pXuaRft6A339uuIQeoeH5qeSKRVTl32L0gdz\n" +
				"2ZivLwZXW+cqvftVW1tvEHvzJFyxeTW3fCUeCQsebLnA2qRa07RkxTo6Nf244mWW\n" +
				"RDodcoHEfDUSbxfTZ6IExSojSIU2RnD6WllYWFdD1GFpBJOmQB8rAc8wJIBdHFdQ\n" +
				"nX8Ttl7hZ6rtgqEYMzYVMuJ2F2r1HSU1zSAvwpdYP6rRGFRJEfdA9mm3WKfNLSc5\n" +
				"cljz0X/TXy0vVlAV95l9qcfFzPmrkNIst9FZSwpvB49LyAVke04FQPPwLgVH4gph\n" +
				"iJH3jvZ7I+J5lS8VAgMBAAGjUDBOMB0GA1UdDgQWBBTTyP6Cc5HlBJ5+ucVCwGc5\n" +
				"ogKNGzAfBgNVHSMEGDAWgBTTyP6Cc5HlBJ5+ucVCwGc5ogKNGzAMBgNVHRMEBTAD\n" +
				"AQH/MA0GCSqGSIb3DQEBCwUAA4IBAQAvMS4EQeP/ipV4jOG5lO6/tYCb/iJeAduO\n" +
				"nRhkJk0DbX329lDLZhTTL/x/w/9muCVcvLrzEp6PN+VWfw5E5FWtZN0yhGtP9R+v\n" +
				"ZnrV+oc2zGD+no1/ySFOe3EiJCO5dehxKjYEmBRv5sU/LZFKZpozKN/BMEa6CqLu\n" +
				"xbzb7ykxVr7EVFXwltPxzE9TmL9OACNNyF5eJHWMRMllarUvkcXlh4pux4ks9e6z\n" +
				"V9DQBy2zds9f1I3qxg0eX6JnGrXi/ZiCT+lJgVe3ZFXiejiLAiKB04sXW3ti0LW3\n" +
				"lx13Y1YlQ4/tlpgTgfIJxKV6nyPiLoK0nywbMd+vpAirDt2Oc+hk\n" +
				"-----END CERTIFICATE-----";
		return new Saml2X509Credential(
				x509Certificate(certificate),
				VERIFICATION
		);
	}

	private X509Certificate x509Certificate(String source) {
		try {
			final CertificateFactory factory = CertificateFactory.getInstance("X.509");
			return (X509Certificate) factory.generateCertificate(
					new ByteArrayInputStream(source.getBytes(StandardCharsets.UTF_8))
			);
		} catch (Exception e) {
			throw new IllegalArgumentException(e);
		}
	}

	private Saml2X509Credential getSigningCredential() {
		String key = "-----BEGIN PRIVATE KEY-----\n" +
				"MIICeAIBADANBgkqhkiG9w0BAQEFAASCAmIwggJeAgEAAoGBANG7v8QjQGU3MwQE\n" +
				"VUBxvH6Uuiy/MhZT7TV0ZNjyAF2ExA1gpn3aUxx6jYK5UnrpxRRE/KbeLucYbOhK\n" +
				"cDECt77Rggz5TStrOta0BQTvfluRyoQtmQ5Nkt6Vqg7O2ZapFt7k64Sal7AftzH6\n" +
				"Q2BxWN1y04bLdDrH4jipqRj/2qEFAgMBAAECgYEAj4ExY1jjdN3iEDuOwXuRB+Nn\n" +
				"x7pC4TgntE2huzdKvLJdGvIouTArce8A6JM5NlTBvm69mMepvAHgcsiMH1zGr5J5\n" +
				"wJz23mGOyhM1veON41/DJTVG+cxq4soUZhdYy3bpOuXGMAaJ8QLMbQQoivllNihd\n" +
				"vwH0rNSK8LTYWWPZYIECQQDxct+TFX1VsQ1eo41K0T4fu2rWUaxlvjUGhK6HxTmY\n" +
				"8OMJptunGRJL1CUjIb45Uz7SP8TPz5FwhXWsLfS182kRAkEA3l+Qd9C9gdpUh1uX\n" +
				"oPSNIxn5hFUrSTW1EwP9QH9vhwb5Vr8Jrd5ei678WYDLjUcx648RjkjhU9jSMzIx\n" +
				"EGvYtQJBAMm/i9NR7IVyyNIgZUpz5q4LI21rl1r4gUQuD8vA36zM81i4ROeuCly0\n" +
				"KkfdxR4PUfnKcQCX11YnHjk9uTFj75ECQEFY/gBnxDjzqyF35hAzrYIiMPQVfznt\n" +
				"YX/sDTE2AdVBVGaMj1Cb51bPHnNC6Q5kXKQnj/YrLqRQND09Q7ParX0CQQC5NxZr\n" +
				"9jKqhHj8yQD6PlXTsY4Occ7DH6/IoDenfdEVD5qlet0zmd50HatN2Jiqm5ubN7CM\n" +
				"INrtuLp4YHbgk1mi\n" +
				"-----END PRIVATE KEY-----";
		String certificate = "-----BEGIN CERTIFICATE-----\n" +
				"MIICgTCCAeoCCQCuVzyqFgMSyDANBgkqhkiG9w0BAQsFADCBhDELMAkGA1UEBhMC\n" +
				"VVMxEzARBgNVBAgMCldhc2hpbmd0b24xEjAQBgNVBAcMCVZhbmNvdXZlcjEdMBsG\n" +
				"A1UECgwUU3ByaW5nIFNlY3VyaXR5IFNBTUwxCzAJBgNVBAsMAnNwMSAwHgYDVQQD\n" +
				"DBdzcC5zcHJpbmcuc2VjdXJpdHkuc2FtbDAeFw0xODA1MTQxNDMwNDRaFw0yODA1\n" +
				"MTExNDMwNDRaMIGEMQswCQYDVQQGEwJVUzETMBEGA1UECAwKV2FzaGluZ3RvbjES\n" +
				"MBAGA1UEBwwJVmFuY291dmVyMR0wGwYDVQQKDBRTcHJpbmcgU2VjdXJpdHkgU0FN\n" +
				"TDELMAkGA1UECwwCc3AxIDAeBgNVBAMMF3NwLnNwcmluZy5zZWN1cml0eS5zYW1s\n" +
				"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDRu7/EI0BlNzMEBFVAcbx+lLos\n" +
				"vzIWU+01dGTY8gBdhMQNYKZ92lMceo2CuVJ66cUURPym3i7nGGzoSnAxAre+0YIM\n" +
				"+U0razrWtAUE735bkcqELZkOTZLelaoOztmWqRbe5OuEmpewH7cx+kNgcVjdctOG\n" +
				"y3Q6x+I4qakY/9qhBQIDAQABMA0GCSqGSIb3DQEBCwUAA4GBAAeViTvHOyQopWEi\n" +
				"XOfI2Z9eukwrSknDwq/zscR0YxwwqDBMt/QdAODfSwAfnciiYLkmEjlozWRtOeN+\n" +
				"qK7UFgP1bRl5qksrYX5S0z2iGJh0GvonLUt3e20Ssfl5tTEDDnAEUMLfBkyaxEHD\n" +
				"RZ/nbTJ7VTeZOSyRoVn5XHhpuJ0B\n" +
				"-----END CERTIFICATE-----";
		PrivateKey pk = RsaKeyConverters.pkcs8().convert(new ByteArrayInputStream(key.getBytes()));
		X509Certificate cert = x509Certificate(certificate);
		return new Saml2X509Credential(pk, cert, SIGNING, DECRYPTION);
	}
}
